1. Field of the Invention
The present invention relates to an improved assembly for controlling the ground speed of an off-road vehicle and, more specifically, relates to an improved transmission linkage which provides an intermediate shaft plate which serves as a centralized location for joining a ground speed and direction control assembly capable of both hand and foot control, as well as a neutral return assembly to a transmission.
2. Description of Related Art
It is well known to provide off-road vehicles, specifically lawn tractors, lawn and garden tractors, and front-mount mowers with systems for controlling their ground speed. Typically, variable speed transmissions such as hydrostatic transmissions or continuously variable transmissions utilized in off-road vehicles such as those listed above have used different combinations of hand and foot controls to select the direction of travel and to control the relative vehicle speed.
Conventional systems utilized to control the ground speed of the types of off-road vehicles mentioned above include a hand lever controls, a treadle pedal, or a dual pedal side-by-side system (such as that disclosed in U.S. Pat. No. 4,759,417 dated Jul. 26, 1988 issued to Wanie et al., the disclosure of which is hereby incorporated by reference).
The pedal systems are often coupled with a hand-operated "cruise control" lever which is generally used to maintain a specified forward speed, eliminating the need for constant application of foot pressure to keep the vehicle moving forward at a desired rate of speed.
Off-road vehicles are also commonly provided with a neutral return which will place a transmission in neutral (or disengage the transmission) when a brake is applied.
The various systems involved in controlling a variable speed transmission of such a vehicle require a number of mechanical linkages. Where foot and hand controls are used in conjunction with a neutral return, the linkages and their attachments to each other are often complex, difficult to service and to modify for special needs of operators.
Accordingly, there is a need for an improved assembly for controlling the ground speed and direction of travel of maneuverable off-road vehicles having variable speed transmissions such as variable speed hydrostatic transmissions; which provides a centralized point of attachment to the transmission of hand and foot controls, as well as a neutral return system.